A 55-year-old male patient presents to a dental clinic complaining of inability to use complete removable dentures fabricated a week ago. The patient also presents with muscle pain in the region of the temporomandibular joint, tooth chatter during a conversation, and difficult biting on food. Objectively: the face is elongated, nasolabial and labiomental folds are flattened, the chin is retruded, the lips do not close. What is the cause of these disorders?